In this learning activity you'll factor problems using the difference of two perfect squares.

In this interactive object, learners demonstrate the proper tightening sequence for mechanically joining two mating surfaces.

In this screencast, you'll review definitions of To, Too, and Two and review practice sentences.

In this animated object, learners examine the signals produced by sourcing and sinking two-wire sensors. A brief quiz completes the activity.

Learners examine the basic types of dimensioning including unidirectional and aligned systems, and linear, aligned, angled, arrowless, chain, datum, chart, tabular, radius, diameter, typical, and reference dimensions.

The student reviews definitions of to/too/two and completes a practice exercise.

The learner will understand the two methods used to create a phase shift in current between two windings.

In this animated activity, learners observe how a two-roll metering system operates.

Learners complete two exercises. In the first quiz, they divide viruses into two categories: RNA and DNA. They later match each virus with the disease it causes.

In this learning activity you'll solve systems of two linear equations in two unknowns by determinants.

Learners examine how the two-roll metering system works.

In this interactive object, students explore the basic elements and common terms associated with dimensions and leaders. A quiz completes the activity.

2D and 3D views used to help convey information from a drafter or designer to the welder are provided. This activity will focus on a mounting wedge. A short quiz to test your ability to correctly read this information follows.

In this animated activity, learners examine how organs are visualized in three dimensions. The terms “longitudinal,” “cross,” “transverse,” “horizontal,” and “sagittal” are defined. Students test their knowledge of the location of abdominal pelvic cavity organs in two drag-and-drop exercises.

In this learning activity you'll explore family structure then enter terms in a grid identifying if that family structure is determined by females, males, or both.

In this interactive object, learners examine the neuron pathway into and out of the spinal cord. They complete the activity by testing their knowledge of vocabulary and the location of spinal cord structures.

Learners use two calculations to prepare a graphical solution to the biasing of bipolar junction transistors and junction field effect transistors. This method eliminates the problem of having to re-calculate the operational Q point when dealing with hard saturation.

Learners review the three formulas for power and work 12 problems. In each of the problems, students are given two of the three variables (voltage, resistance, or current) and asked to solve for power. Immediate feedback is provided.

Learners examine dew point and the two types of humidity values, absolute and relative, along with the types of instruments used to measure them. The activity includes a video clip and a quiz.

Learners solve two sample problems for a numerical reasoning assessment.